Zonisamide effective for weight loss in women
The Journal of Family Practice. 2003 August;52(8):587-604
August 1, 2003|The Journal of Family Practice
Author and Disclosure Information
- BACKGROUND: Zonisamide is an antiepileptic medication with a common side effect of causing significant weight loss. This study was conducted to assess the efficacy of using zonisamide for weight loss alone in obese adults.
- POPULATION STUDIED Sixty adults from an outpatient clinic population and those responding to flyers were enrolled. Participants were aged 21 to 50 years, with a mean body-mass index of 36.3 and mean age of 37 years. Subjects were 92% female; 48% were African Americans and 52% Caucasians.
- STUDY DESIGN AND VALIDITY: Subjects were randomized in a double-blind fashion (allocation assignment concealed) to receive either zonisamide or identical placebo. All participants were also prescribed a hypocaloric diet (500 kcal/d deficit). Zonisamide therapy was started at 100 mg/d orally and gradually titrated to 600 mg/d.
- OUTCOMES MEASURED: The primary outcome measured was change in absolute body weight. Secondary outcomes included percent weight change and the number of participants in each group to reach a weight loss of at least 5% and 10% of baseline body weight. Other measures included adverse treatment effects and an Impact of Weight on Quality of Life (IWQOL) questionnaire.
- RESULTS: In the initial phase of the trial, the zonisamide group lost significantly more weight than the placebo group (mean 5.9 kg vs 0.9 kg; P<.001). A total of 57% of patients in the zonisamide group vs 10% in the placebo group lost at least 5% of their initial body weight, and 23% of those in the zonisamide group vs 0% in the placebo group lost at least 10% of initial body weight (P=.05). After the extension phase, the zonisamide group had a mean weight loss of 9.2 kg vs 1.5 kg for the placebo group.
PRACTICE RECOMMENDATIONS
Zonisamide (Zonegran), in conjunction with a reduced-calorie diet (deficit of 500 kcal/d), resulted in an additional mean 5-kg (11-pound) weight loss compared with diet alone. This regimen was well-tolerated in obese female patients. Further evaluation of long-term side effects and continued weight loss beyond 32 weeks is needed.
